MEASUREMENT OF PRICE RISK IN REVENUE INSURANCE: IMPLICATIONS OF DISTRIBUTIONAL ASSUMPTIONS

A variety of crop revenue insurance programs have recently been introduced. A critical component of revenue insurance contracts is quantifying the risk associated with stochastic prices. Forward-looking, market-based measures of price risk which are often available in form of options premia are preferable. Because such measures are not available for every crop, some current revenue insurance programs alternatively utilize historical price data to construct measures of price risk. This study evaluates the distributional implications of alternative methods for estimating price risk and deriving insurance premium rates. A variety of specification tests are employed to evaluate distributional assumptions. Conditional heteroskedasticity models are used to determine the extent to which price distributions may be characterized by nonconstant variances. In addition, these models are used to identify variables which may be used for conditioning distributions for rating purposes. Discrete mixtures of normals provide flexible parametric specifications capable of recognizing the skewness and kurtosis present in commodity pricesRisk and Uncertainty,

Private Regional Universities as Alternatives to World Class Universities: Achievable Goals for Developing Nations

<p style="margin-bottom: 0in;">A predominant discussion in Asian higher education is the identification and value of world class universities. The pressure to develop world class universities is coming from two sectors. First, the governments themselves see a world class university as a critical prerequisite to moving innovation into the economy and thereby moving the economy ahead and also as a source of status and prestige for the country. Second, parents who are keenly aware of the best universities in the world apply pressure to have equally prestigious universities in their native countries. Although world class universities move the frontiers of knowledge ahead, and clearly help their nation by providing a source of scientists and educated professionals via their graduate schools, many students, especially undergraduates, may be better served by regional universities with emphasis on pedagogy at the undergraduate level. The purpose of this article is to propose that regional private universities provide an alternative, not a replacement, to large research universities as a meaningful investment for both the regional economy and the student.</p

Palmitoylation of Desmoglein 2 Is a Regulator of Assembly Dynamics and Protein Turnover.

Desmosomes are prominent adhesive junctions present between many epithelial cells as well as cardiomyocytes. The mechanisms controlling desmosome assembly and remodeling in epithelial and cardiac tissue are poorly understood. We recently identified protein palmitoylation as a mechanism regulating desmosome dynamics. In this study, we have focused on the palmitoylation of the desmosomal cadherin desmoglein-2 (Dsg2) and characterized the role that palmitoylation of Dsg2 plays in its localization and stability in cultured cells. We identified two cysteine residues in the juxtamembrane (intracellular anchor) domain of Dsg2 that, when mutated, eliminate its palmitoylation. These cysteine residues are conserved in all four desmoglein family members. Although mutant Dsg2 localizes to endogenous desmosomes, there is a significant delay in its incorporation into junctions, and the mutant is also present in a cytoplasmic pool. Triton X-100 solubility assays demonstrate that mutant Dsg2 is more soluble than wild-type protein. Interestingly, trafficking of the mutant Dsg2 to the cell surface was delayed, and a pool of the non-palmitoylated Dsg2 co-localized with lysosomal markers. Taken together, these data suggest that palmitoylation of Dsg2 regulates protein transport to the plasma membrane. Modulation of the palmitoylation status of desmosomal cadherins can affect desmosome dynamics

MEASUREMENT OF PRICE RISK IN REVENUE INSURANCE: IMPLICATIONS OF DISTRIBUTIONAL ASSUMPTIONS

A variety of crop revenue insurance programs is now available. These programs require measurement of price risk. This article investigates the appropriateness of distributional assumptions underlying current and proposed alternative actuarial methods. Our results find that prices are best modeled using a flexible mixture of normals distribution.Demand and Price Analysis, Risk and Uncertainty,

Lithium atom interferometer using laser diffraction : description and experiments

We have built and operated an atom interferometer of the Mach-Zehnder type. The atomic wave is a supersonic beam of lithium seeded in argon and the mirrors and beam-splitters for the atomic wave are based on elastic Bragg diffraction on laser standing waves at 671 nm. We give here a detailed description of our experimental setup and of the procedures used to align its components. We then present experimental signals, exhibiting atomic interference effects with a very high visibility, up to 84.5 %. We describe a series of experiments testing the sensitivity of the fringe visibility to the main alignment defects and to the magnetic field gradient.Comment: 8 avril 200

Analytical Approximations of Critical Clearing Time for Parametric Analysis of Power System Transient Stability

An analytic approximation for the critical clearing time (CCT) metric is derived from direct methods for power system stability. The formula has been designed to incorporate as many features of transient stability analysis as possible such as different fault locations and different post-fault network states. The purpose of this metric is to analyse trends in stability (in terms of CCT) of power systems under the variation of a system parameter. The performance of this metric to measure stability trends is demonstrated on an aggregated power network, the so-called two machine infinite bus network, by varying load parameters in the full bus admittance matrix using numerical continuation. The metric is compared to two other expressions for the CCT which incorporate additional non-linearities present in the model